羽扇豆根瘤类菌体周膜ATP酶的特性分析

Characterization of the peribacteroid membrane ATPase of lupin root nodules.

作者信息

Domigan N M, Farnden K J, Robertson J G, Monk B C

机构信息

Department of Biochemistry, University of Otago, Dunedin, New Zealand.

出版信息

Arch Biochem Biophys. 1988 Aug 1;264(2):564-73. doi: 10.1016/0003-9861(88)90322-0.

DOI:10.1016/0003-9861(88)90322-0

PMID:2969700

Abstract

Peribacteroid membranes can be isolated in essentially pure form from 20-day lupin root nodules by osmotic shock of the purified membrane enclosed bacteroids. The ATPase (EC 3.6.1.3) associated with this membrane has an acid pH optimum (5.25) and is specific for ATP (Mg-ATP Km = 0.16 mM). The enzyme activity requires magnesium or manganese ions, is slightly stimulated by the cations potassium and rubidium, and is inhibited by vanadate, diethylstilbestrol, N,N'-dicyclohexylcarbodiimide, fluoride, molybdate, and calcium. Molybdate and fluoride sensitivity do not in this case indicate the presence of significant nonspecific phosphatase activity. The ATPase is not inhibited by oligomycin, azide, or the soluble carbodiimide 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide. In some respects the lupin peribacteroid membrane ATPase appears to differ from the plasma membrane ATPase of other plants.

摘要

通过对纯化的膜包被类菌体进行渗透休克处理，可从20日龄羽扇豆根瘤中以基本纯的形式分离出类菌体周膜。与该膜相关的ATP酶（EC 3.6.1.3）的最适酸性pH值为5.25，且对ATP具有特异性（Mg-ATP的Km值为0.16 mM）。该酶活性需要镁离子或锰离子，钾离子和铷离子对其有轻微刺激作用，而钒酸盐、己烯雌酚、N,N'-二环己基碳二亚胺、氟化物、钼酸盐和钙离子对其有抑制作用。在这种情况下，钼酸盐和氟化物的敏感性并不表明存在显著的非特异性磷酸酶活性。该ATP酶不受寡霉素、叠氮化物或可溶性碳二亚胺1-乙基-3-(3-二甲基氨基丙基)碳二亚胺的抑制。在某些方面，羽扇豆类菌体周膜ATP酶似乎与其他植物的质膜ATP酶不同。